Flash Flood Prediction Program

Time: 438 PM Fri July 15, 2022 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGES CONTINUE VALID UNTIL 9:00 PM - The Message 2 for Boulder County will remain in effect until 9:00 PM. Message 1's for all other Counties within the District will also remain valid until 9:00 PM. - Thunderstorms have initiated in and near the District with prime time through 8:00 PM. Typical storms are producing light to briefly moderate rain as the District has yet to experience a stronger storm. If the trend holds storms will continue to be weak to moderate in nature for most areas, however a strong thunderstorm cannot be ruled out which will be capable of producing heavy rainfall that may lead to excessive runoff. - Upper level steering winds are from SW to NE at around 15mph. One round of storms E of I-25 will clear the District in the next 60-90 minutes with another wave approaching from the SW keeping chances for storms into the evening. STORM RAINFALL POTENTIAL AND DURATION: More typical weak to moderate thunderstorms will produce rainfall rates of 0.1-0.5" in 10-30 minutes. Strong thunderstorms will will have the potential to produce rainfall rates of 0.5-1.5" in 10-30 minutes. WORST CASE SCENARIO: A large thunderstorm complex or a nearly stationary strong thunderstorm cell may result in up to 2.5" of rain in 60-90 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME the City of Aurora 1 1200 PM TO 900 PM 100 PM TO 800 PM Arapahoe County 1 1200 PM TO 900 PM 100 PM TO 800 PM DIA 1 1200 PM TO 900 PM 100 PM TO 800 PM Denver County 1 1200 PM TO 900 PM 100 PM TO 800 PM Adams County 1 1200 PM TO 900 PM 100 PM TO 800 PM Douglas County 1 1200 PM TO 900 PM 100 PM TO 800 PM Broomfield County 1 1200 PM TO 900 PM 100 PM TO 800 PM Jefferson County 1 1200 PM TO 900 PM 100 PM TO 800 PM Boulder County 2 1200 PM TO 900 PM 100 PM TO 800 PM Arvada 1 1200 PM TO 900 PM 100 PM TO 800 PM Wheat Ridge 1 1200 PM TO 900 PM 100 PM TO 800 PM Lakewood 1 1200 PM TO 900 PM 100 PM TO 800 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED Arapahoe Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED Boulder Current TO 900 PM FRI 0.1" (80%) to 0.5" (40%) to 1.5" (5%) ISSUED Broomfield Current TO 900 PM FRI 0.1" (80%) to 0.5" (40%) to 1.5" (5%) ISSUED Denver Current TO 900 PM FRI 0.1" (80%) to 0.5" (40%) to 1.5" (5%) ISSUED Douglas Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED Jefferson Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED Foothills above 6500ft       Boulder Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED Douglas Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED Jefferson Current TO 900 PM FRI 0.1" (90%) to 0.5" (50%) to 1.5" (10%) ISSUED MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]